Humans utilize the inherent biomechanical compliance present in their fingers for increased stability and dexterity during manipulation tasks. While series elastic actuation has been explored, little research has been performed on the role of joint compliance arranged in parallel with the actuators. The goal of this thesis is to demonstrate, through simulation studies and experimental analyses, the advantages gained by employing human-like passive compliance in finger joints when grasping. We first model two planar systems: a single 2-DOF (degree of freedom) finger and a pair of 2-DOF fingers grasping an object. In each case, combinations of passive joint compliance and active stiffness control are implemented, and the impulse disturbance responses are compared. The control is carried out at a limited sampling frequency, and an energy analysis is performed to investigate stability. Our approach reveals that limited controller frequency leads to increased actuator energy input and hence a less stable system, and human-like passive parallel compliance can improve stability and robustness during grasping tasks. Then, an experimental setup is designed consisting of dual 2-DOF tendon-driven fingers. An impedance control law for two-fingered object manipulation is developed, using a novel friction compensation technique for improved actuator force control. This is used to experimentally quantify the advantages of parallel compliance during dexterous manipulation tasks, demonstrating smoother trajectory tracking and improved stability and robustness to impacts. / text

Continuum robots are the biologically inspired robots that mimic the behaviors of mammalian tongues, elephant trunks, and octopus arms. These robots feature a backboneless structure similar to their biological counterparts, such as termed muscular hydrostats. The drawbacks of two existing designs are examined and a new mechanical design that uses a single latex rubber tube as the central member is proposed, providing a design that is both simple and robust. Next, a novel verification procedure is applied to examine the validity of the proposed model in two different domains of applicability. A two-level electrical control scheme enables rapid prototyping and can be used to control the continuum robot remotely with a joystick via a Local Area Network (LAN). Next, a new geometrical approach to solve inverse kinematics for continuum type robot manipulators is introduced. Given the tip of a three-section robot, end-points of section 1 and section 2 are computed, and a complete inverse kinematics solution for a multisection continuum robot is then achieved by applying inverse kinematics to each section continuum trunk. Moreover, the algorithm provides a solution space rather than a single valid solution. Finally, the techniques involved in visualization of AirOctor/OctArm in 3D space in real-time are discussed.The algorithm has been tested with several system topologies.

Continuum robots mimic the principle of a special biological structure known as the muscular hydrostat. These robots have an ability to bend at any location on along its backbone and have potential applications in disaster relief, medical surgeries and nuclear waste disposal. This thesis presents the modeling and verification of a multi-section continuum robot by applying the Cosserat theory of rods. Next, 2D verification is performed on a continuum robot based on a backbone composed of a nickel titanium alloy. In addition, the thesis develops the theoretical foundations for a cable-driven continuum robot by studying the effects of cable guide mass which cause additional deformation of the robot The results of this thesis show that the multi-section model is accurate within 3.4% in predicting the Cartesian tip coordinates, and the model with the cable guides accurate within 1.26% error in predicted versus the observed Cartesian tip coordinates of the backbone.

京都大学 / 新制・課程博士 / 博士(工学) / 甲第23505号 / 工博第4917号 / 新制||工||1768(附属図書館) / 京都大学大学院工学研究科機械理工学専攻 / (主査)教授 松野 文俊, 教授 泉田 啓, 教授 小森 雅晴 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM

No description available.

Continuum robots are biologically inspired robots that capture the extraordinary abilities of biological structures such as elephant trunks, octopus tentacles, and mamma-lian tongues. They are given the term continuum robots due to their ability to bend conti-nuously rather than at specific joints such as with traditional rigid link robots. They are used in applications such as search and rescue operations, nuclear reactor repairs, colo-noscopies, minimal invasive surgeries, and steerable needles. In this thesis, a model that predicts the shape of a continuum robot is presented and verified. A verification system to verify the validity and accuracy of the model is presented which allows easy and accu-rate measurement of a continuum robot tip position. The model was verified against a flexible rod, the core component of a continuum robot, resulting in an accuracy of 0.61%. Finally, this thesis introduces a novel robot design, consisting of a single rod for the backbone which can be manipulated by applying external forces and torques.

No description available.